"Yet it is the first time that Russia suffered not from nameless terrorists (mostly of Chechen origin). Now the terrorists have a name on them - ISIS. And the more suffering is yet to come." I think ISIS gave the perfect opportunity for Putin to come back into Egypt, by the back door. In the mean time, the Syrian recapture one strategic point, if we have to believe news from Russia, which I tend to in this situation as US and EU would be so happy to show if it was a lie.
Point is Russia didn't suffer. Russian did. ISIS can't attack Russia and now, as Fragony pointed out, are probably waiting for incoming retaliations.
As more to come, perhaps, but France was attacked by Muslim terrorists. And they are only really one example of a successful terrorist succeeding his political aim: Gavrilo PRINCIP, and it took all the great willingness of the Central Empires to help him.
ISIS is destined to the bin of History, as soon as great powers will decide the play time is finish.